The present disclosure relates to the electrical, electronic, and computer arts, and, more particularly, to electrical antifuses for use in the semiconductor industry.
Antifuse structures have been used in the semiconductor industry for memory-related applications such as filed programmable gate arrays and programmable read-only memories. Such structures typically include a material that initially has a high electrical resistance but can be converted into a lower electrical resistance. After a high voltage programming process, the device/circuit becomes electrically conductive/open through a dielectric breakdown phenomenon. Once programmed, the programmed state of an electrical antifuse or fuse does not revert to its original state. In other words, the programmed state is intended to be irreversible. An antifuse is typically fused by applying a sufficient voltage across the antifuse structure. The voltage causes the structure to fuse together, resulting in the permanent “open” state.
The breakdown of a dielectric layer such as an oxide by the application of a sufficient electric field is one technique for forming an antifuse. Prior to programming, the integrity of the dielectric layer is maintained and the antifuse structure exhibits high electrical resistance. The application of a high dielectric field across the two electrodes of the antifuse that adjoin the dielectric layer induces a rupture, thereby causing reduction of the electrical resistance across the two electrodes.